Medical researchers and teachers use statistical analysis in diverse medical fields, yet current statistical software systems offer little help to people untrained in biostatistics. The applicants propose to develop ADVISE, a visual environment for data analysis, which has extensive guidance capabilities. The goal is to allow medical researchers who are not biostatisticians to examine, model and make inferences from their own data. ADVISE creates a direct manipulation interface for statistical analysis. Using data and function icons on an interactive workmap the user can construct, modify and save an analysis. ADVISE achieves an appealing uniformity through this visual analysis paradigm. Every stage in the analysis can be visualized by simply pointing at the icon, and an analysis can be modified simply by changing icon parameters. Guidance is embedded into every aspect of the system: context-sensitive hypertext gives help in using the system, setting parameters, and interpreting results, and on-line documentation gives "just-in-time" statistical advice. ADVISE is extensible; hence, it provides an enabling technology for rapid and easy transfer of new statistical methods into the hands of medical researchers. ADVISE is entirely modular and as technology advances, it is possible to upgrade the statistical, hypertext, database, and graphics technology.